This evening i noticed my cat eating, (She's 11 years old, btw) and she was eating fine, and then she took another bite, and kind of flinched? Not quite, but she just looked a little uncomfortable. She stopped for a few seconds, and then went back to eating.

I called her to me and then looked in her mouth. (which was very difficult, let me tell you.)
And i noticed her teeth, right behind her canines, (towards the back) were really small, Almost less then an inch there (which I'm led to believe is normal in senior cats?) but i noticed on the bottom right, one of them was missing, or covered by gum. It was a little red, not super inflamed, but just a little red, like it was recently lost.

Once she stops being mad at me I'm going to look again, poke it and see if i feel a tooth there or not. I can try and get pictures if i need,

i was able to look at the missing tooth spot, and it feels like it has a little lump there. Its probably about _ big (actually _ big) and feels squishy and not super hard- like, it doesnt feel like a tooth

I havent noticed any eating issues before this, (she could have just bitten her tongue, but I'm concerned about the tooth)

She is drinking lots of water,

I would just put her on soft food, but she will NOT eat it.
I swear, i have the worlds pickiest cat, she hates wet food (all flavors, all the brands we've tried), She hates fish, or meats. Pretty much most of everything normal cats like, shes hates (discluding milk products)

She is currently on Friskies, i believe.

I am VERY concerned about having to get her a surgery. She is an older cat, and i havent been to the vet to get her heart checked or anything. I would love to, but I'm only sixteen, and my parents are very old fashioned and think vet trips are stupid. (We are tight for money right now also.)

She still acts like a younger cat, every so often she'll get her crazy moments where she'll run around the house like crazy, Shes always by my side, (Rarely, if ever doesnt bother to follow me around)

But if you think she needs to go to the vet, i dont have a job but i do have some money saved for college i can dip into if i need (its not a lot mind you)

My biggest fear is loosing this cat. I have had her since i was four, and i cannot imagine a life without her.

At 11 your cat definitely needs to have her teeth checked by a vet. She is not too old to be put under for a teeth cleaning/pulling, we had a cat done this year that is 14. Explain to your parents that they go to a dentist when their teeth hurt, so should cats. Maybe you could tell them that a vet visit for her would be your Christmas present this year, what a good present it would be to have your best friend healthy at Christmas.

I've taken my dogs and my younger barn cats (when they were getting fixed)
But she is a different story.

Whenever she leaves the house (even just me holding her, on the deck) she goes crazy.

Normally, she is the sweetest thing, who loves cuddles and purring and what not, but as soon as she is in a new environment she is insane. She hisses, bites growls, at everyone. She completely looses her head and forgets how to behave.

Example: About a month ago, we had a fire start in our kitchen. I grabbed her, and ran to my sisters house, (which is on the same property as ours, just across the yard) The second we left the door, she was growling and hissing and trying to get away from me. I left her there, until everything was settled at our house.
When i got her back, she bit, hissed all the way home, and as SOON as we stepped in the door she stopped everything, and acted like a normal cat.

First, find a carrier to take her in. Trying to carry her loose or on a leash is just asking for trouble. Second, ask your vet what they do for aggressive cats. My Misty gets rolled in a towel due to her effort to bite all vets in existence. They even have a sort of mask that they can put over her muzzle if necessary to prevent bites (although that does make it hard to check teeth).
Maybe look at the mouth of one of the younger kitties and compare it to your older cat's to see if she really is missing a tooth?
Honestly, you really can't get a cat like this to behave. Just remember, it's fear, not really hatred. She will be much happier if her teeth stop hurting (if that's the problem). Let the vet know ahead of time, then they will be prepared, don't surprise them. They deal with other out of control animals, they just need to know what is coming in.
If she will eat, take treats and see if you can make the experience more pleasant. (Our boys stubbornly refuse all treats while at the vet. Misty will attempt to bite all employees, then settle down in her crate to munch on treats.)

I obviously do want to take her to the vet, but watching her eat, she doesnt seem to be in any pain, besides that one time (and for all i know she could have bitten her tongue)
If i continue to notice no change (for the worse) I'll take her in after Christmas. As things are insane right now

Cats can suffer from tooth resorption, or FORL (Feline Odontoclastic Resorptive Lesions). It can affect any adult cat, not just seniors. This is VERY painful. Essential the tooth starts to be broken down and reabsorbed. It usually starts out looking like a small hole or cavity, and by the end, looks like a bump of gum tissue.

At a certain point there is no treatment. The resorption just has to run its course. In which case, the veterinarian may choose to use painkillers and anti inflammatory drugs to help your kitty feel a bit more comfortable. Before this point, the only treatment is extraction (removal).

Diagnosis can usually be made on visual inspection. Whether the teeth should be pulled can only be determined with dental x-rays.

Not saying that your cat has this, but it's definitely something to consider. In the mean time you can soften her kibble up with a little bit of warm water, however moist/wet food should not be left out for more than approx. 30 minutes, as it makes for an amazing bacteria breeding ground.

As for your kitty going crazy, you can try any of the pheromone products on the market (An example is a product called Feliway). These work to calm anxious kitties using natural responses. Definitely transport your cat in a kennel, not a soft one.... they suck butt. Hard kennels with a removable top work the best, and often your vet will have some kicking around. You can try calling and see if they would be willing to lend you one Everyone that has responded thus far is correct, the veterinary staff are experienced in dealing with the most unruly of animals, but it's always better for the animal if you can make the trip/experience as stress free as possible.

I attached a feline dental chart for you (Its not the best one I've ever seen, sorry about that). This way you can take a look at your kitties teeth and have a better idea if what your seeing is a space where a tooth should be

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